Parametric Study of the Morphological Proprieties of HT-PEMFC Components for Effective Membrane Hydration

A 1D non-isothermal model has been developed to study the optimum morphological properties of HT-PEMFC components that will help the catalyst layer retain water vapor generated by the electrochemical reaction and that delivered by the feed gases. The use of a microporous layer (MPL) helps retain water generated in the catalyst layer (CL), and the effectiveness of the MPL in retaining water vapor in the CL increases the MPL pore size and porosity are reduced. Reducing the GDL porosity is found to help retain more water in the CL but the pore sizes and porosity of the PEMFC components should not be too small, so as to avoid increased O2 concentration overpotentials. The optimum values of MPL and GDL porosity depend on the operating conditions such as the cell voltage, operating pressure, and inlet relative humidity. VC 2011 The Electrochemical Society. [DOI: 10.1149/1.3569711] All rights reserved. Manuscript submitted January 26, 2011; revised manuscript received March 1, 2011. Published April 12, 2011. It is widely recognized that the development of proton-exchange-membrane fuel cells (PEMFC) that can be operated at a temperature higher than 100C will help address some of the key issues and short-comings of the low-temperature PEMFC.1 When the PEMFC is oper-ated above 100C at near atmospheric pressure, water exists in the vapor phase only in the pores of gas diffusion layer and catalyst layer